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PubMed1995

Recognition and liking of tobacco and alcohol advertisements among adolescents: relationships with susceptibility to substance use.

BACKGROUND: Exposure to tobacco and alcohol advertising has been associated with adolescent substance use. However, it is not clear whether favorable reactions to advertising are an antecedent to or a consequence of substance use. This study investigated relationships between adolescents' levels of susceptibility to substance use and their recognition and liking of tobacco and alcohol advertising. METHOD: Eighth-grade students viewed pictures of tobacco and alcohol advertisements with brand names and identifying information obscured, attempted to identify the brand name and type of product being advertised, and rated their liking of the advertisements. Subjects were divided into three substance use status groups: nonsusceptible nonusers (have never used and do not intend to do so), susceptible nonusers (have not used but have not made a firm commitment not to experiment in the future), and users (have tried the substance). RESULTS: Susceptible nonusers liked the tobacco advertisements at a level that was significantly greater than that of the nonsusceptible nonsmokers and comparable to that of the users. Liking of the alcohol advertisements generally increased with alcohol use status. CONCLUSIONS: These results suggest that tobacco advertisements ostensibly targeted to adult smokers may have the effect of recruiting new adolescent smokers.

Adolescent↗

PubMed1978

Interactive control of graphic output devices.

A software package for the support of graphic output was developed. The main feature is the capability to draw graphs in a Cartesian coordinate system. With up to 60 variable parameters, it is problematic to change them interactively. Classical program languages do not support interaction. Subroutines for various kinds of input had to be written. Most important are other subroutines for reading, writing or erasing datasets at runtime, the name of which need not be known before starting a program. According to the problems, different appropriate methods of dialogue were used: the simple sequential dialoque, command languages and, for more complex input, a syntax analyser. The resulting dialogue is very simple and self-explanatory. The users need not have previous experience with computers; the package was accepted quickly and is now in extensive use.

Computers↗

PubMed1982

A randomization list generator for biomedical experiments.

The paper describes RANLST, an interactive program to produce random sequences for randomizing patients or animals to treatments in biomedical experiments. The program allows the user to specify strata, seed value for the random generator, equal or unequal treatment allocation, and unrestricted or restricted randomization. An illustrative example is included.

Animals↗

PubMed1991

Acceptability of the vaginal sheath (Femshield) in Thai couples.

A small survey to assess the perception and experience of current family planning users and their husbands was carried out in a university family planning clinic. Women routinely visiting the clinic were asked to complete a short Screening Form. Fifty-six women responded to the questionnaire concerning their attitude to the Femshield. Eighteen volunteers agreed to enter the study and were given verbal instruction on use of the device. Each volunteer was provided with 3-5 Femshields. Participants were asked to return to the clinic one month after admission. A Husband Form was then sent to the home of the volunteers to assess the attitude of their husbands. Thirteen volunteers returned for the follow-up visit. Fifty Femshields were used. The results showed that the volunteers found the vaginal insertion of the device was acceptable, but the outer and inner rings of the device caused an uncomfortable feeling when having intercourse. The volunteers were more positive to the device than their spouses. The sexual satisfaction of both partners was reduced. A few couples suggested that the device be modified with the bag being smaller and thinner, the outer and inner rings reduced in size and softer, and the device itself being in a prelubricated packet.

Consumer Behavior↗

PubMed1990

Effects of carbamazepine on self-administration of intravenously delivered cocaine in rats.

Carbamazepine (Tegretol) is widely used therapeutically as an anticonvulsant. Based on an hypothesis that links electrical kindling in the limbic system (leading to seizures) to reverse tolerance or sensitivity to cocaine's effects, carbamazepine is being tested as a treatment for human cocaine users. The purpose of this experiment was to examine the effects of carbamazepine on intravenous cocaine self-administration in rats. Rats self-administered intravenously delivered cocaine (0.2 mg/kg) under a fixed-ratio 4 schedule. When cocaine injections reached stable levels, carbamazepine was mixed with the rats' food for 8 days. Three doses of carbamazepine were tested (80, 120, and 160 mg/kg) in different groups of 5 rats each. The rats were later separated into groups with a high (greater than 750 infusions) and a low (500-750 infusions) cocaine baseline. Two control groups of 5 rats each received carbamazepine treatments (120 or 160 mg/kg) and self-administered an orally delivered solution of glucose and saccharin (G + S). At the highest carbamazepine dose in the high cocaine baseline group, carbamazepine reduced cocaine infusions by at least 50 percent and food intake by approximately 25 percent during the 8 days of treatment. Cocaine infusions returned to baseline within 24 hr after the regular diet was restored. Carbamazepine had a minimal effect in groups of rats with lower cocaine baselines. Responding reinforced by the G + S solution was reduced by both the 120 and 160 mg/kg carbamazepine doses. Water intake was not systematically affected by the addition of carbamazepine to the food; however, activity measures were significantly lower in some groups at the higher carbamazepine doses.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1990

Hydrophobic cluster analysis: procedures to derive structural and functional information from 2-D-representation of protein sequences.

Hydrophobic cluster analysis (HCA) [15] is a very efficient method to analyse and compare protein sequences. Despite its effectiveness, this method is not widely used because it relies in part on the experience and training of the user. In this article, detailed guidelines as to the use of HCA are presented and include discussions on: the definition of the hydrophobic clusters and their relationships with secondary and tertiary structures; the length of the clusters; the amino acid classification used for HCA; the HCA plot programs; and the working strategies. Various procedures for the analysis of a single sequence are presented: structural segmentation, structural domains and secondary structure evaluation. Like most sequence analysis methods, HCA is more efficient when several homologous sequences are compared. Procedures for the detection and alignment of distantly related proteins by HCA are described through several published examples along with 2 previously unreported cases: the beta-glucosidase from Ruminococcus albus is clearly related to the beta-glucosidases from Clostridum thermocellum and Hansenula anomala although they display a reverse organization of their constitutive domains; the alignment of the sequence of human GTPase activating protein with that of the Crk oncogene is presented. Finally, the pertinence of HCA in the identification of important residues for structure/function as well as in the preparation of homology modelling is discussed.

Amino Acid Sequence↗

PubMed1991

Drug treatment staff attitudes toward AIDS and workplace transmission of HIV: a survey and follow-up--Spectrum House, Inc.

A growing number of cases of HIV infection and AIDS in the U.S. have been reported among intravenous drug users and their sexual partners. This increase in cases has begun to have a significant impact on substance abuse treatment programs; in addition to the complexities of HIV education and counseling, the staff of such programs must deal with their own fears regarding HIV infection, since many experientially trained staff are, themselves, former IV drug users. Other staff members may experience irrational anxiety about working HIV-infected clients, due to the fear of workplace exposure to the virus. In order to assess the extent and nature of such anxieties among its staff, Spectrum House, Inc., a comprehensive substance abuse treatment program, administered a Staff AIDS Survey in 1986 and again in 1987. Responses reflected a marked decrease in staff anxieties relating to workplace transmission of HIV during the 14-month period between surveys, seemingly related to both the implementation of AIDS education and an increase in contact with HIV positive clients. Those staff members whose contact with HIV positive clients remained infrequent between surveys, however, continued to show higher levels of fear about casual contact and workplace exposure to HIV. These results indicate that increased staff-client interaction may be an effective addition to other forms of staff AIDS education in substance abuse treatment programs.

Acquired Immunodeficiency Syndrome↗

PubMed2005

Imagery of motor actions: differential effects of kinesthetic and visual-motor mode of imagery in single-trial EEG.

Single-trial motor imagery classification is an integral part of a number of brain-computer interface (BCI) systems. The possible significance of the kind of imagery, involving rather kinesthetic or visual representations of actions, was addressed using the following experimental conditions: kinesthetic motor imagery (MIK), visual-motor imagery (MIV), motor execution (ME) and observation of movement (OOM). Based on multi-channel EEG recordings in 14 right-handed participants, we applied a learning classifier, the distinction sensitive learning vector quantization (DSLVQ) to identify relevant features (i.e., frequency bands, electrode sites) for recognition of the respective mental states. For ME and OOM, the overall classification accuracies were about 80%. The rates obtained for MIK (67%) were better than the results of MIV (56%). Moreover, the focus of activity during kinesthetic imagery was found close to the sensorimotor hand area, whereas visual-motor imagery did not reveal a clear spatial pattern. Consequently, to improve motor-imagery-based BCI control, user training should emphasize kinesthetic experiences instead of visual representations of actions.

Adolescent↗

PubMed2004

Human chorionic gonadotrophin and progesterone levels in pregnancies of unknown location.

OBJECTIVE: To evaluate accuracy, user variability and impact of experience on the use of serum hCG and progesterone in women who have a pregnancy of unknown location (PUL's). MATERIALS AND METHODS: This was a retrospective study. Presenting 1932 consecutive women to an Early Pregnancy Unit had a transvaginal scan. The location of the pregnancy could not be found in 189 women (Pregnancy of unknown location, PUL), and so blood was taken to measure serum hCG and progesterone at presentation and subsequently after 48 h, according to the protocol. All women were monitored at regular intervals until the final outcome was known, which was a failing PUL, a viable or failing intra-uterine pregnancy, an ectopic pregnancy or a persisting PUL. The final study group comprised 185 PUL, as four cases of persisting PUL were treated and excluded from the analysis. Five investigators assessed the hormonal data independently. The investigator's experience as defined by the number of years working in obstetrics and gynecology ranged from 2 to 15 years. Each investigator knew the women were clinically stable and that the scan result was consistent with a PUL, i.e. there were no signs of intra- or extra-uterine pregnancy, and there was no hemoperitoneum on TVS. When assessing the PUL's, each investigator was given the hormonal results at time 0 and 48 h for serum hCG and progesterone and asked to classify the PUL's as failing PUL's, immediately viable intra-uterine PUL's and ectopic PUL's. No other clinical information about the women was made available. RESULTS: Complete data 185 women (89%): 102 failing PUL's, 63 immediately viable intra-uterine PUL's and 20 ectopic PUL's (total 185). The most experienced investigator obtained the best accuracy 163/185 (88.1%); not significantly different from those obtained by less experienced investigators (range 85.9-87.6%). Mean correct classification of failing PUL and immediately viable intra-uterine PUL's was 93% (range 89-95%); corresponding value for ectopic PUL's was 42% (range 25-60%). Agreement between observers for classification of failing PUL's and immediately viable intra-uterine PUL's was almost perfect (Cohen's kappa 0.86-0.90), whereas the value for ectopic PUL's group was fair to moderate (Cohen's kappa 0.39-0.67). All 5 investigators misdiagnosed same 35% of ectopic PUL's. CONCLUSIONS: Serum hCG and progesterone levels at defined times can be used to predict the immediate viability of a PUL, but cannot be used reliably to predict its location. Clinical experience does not significantly improve the ability to assess PUL outcome.

Chorionic Gonadotropin↗

PubMedDate not supplied

Self-organization of distributedly represented multiple behavior schemata in a mirror system: reviews of robot experiments using RNNPB.

The current paper reviews a connectionist model, the recurrent neural network with parametric biases (RNNPB), in which multiple behavior schemata can be learned by the network in a distributed manner. The parametric biases in the network play an essential role in both generating and recognizing behavior patterns. They act as a mirror system by means of self-organizing adequate memory structures. Three different robot experiments are reviewed: robot and user interactions; learning and generating different types of dynamic patterns; and linguistic-behavior binding. The hallmark of this study is explaining how self-organizing internal structures can contribute to generalization in learning, and diversity in behavior generation, in the proposed distributed representation scheme.

Artificial Intelligence↗

PubMed1999

Comparative safety, efficacy, and cycle control of Lunelle monthly contraceptive injection (medroxyprogesterone acetate and estradiol cypionate injectable suspension) and Ortho-Novum 7/7/7 oral contraceptive (norethindrone/ethinyl estradiol triphasic). Lunelle Study Group.

An open-label, nonrandomized, parallel, controlled study compared the efficacy, safety, and cycle control of a new monthly injectable contraceptive containing 25 mg of medroxyprogesterone acetate (MPA) and 5 mg of estradiol cypionate (E2C) (MPA/E2C) (Lunelle Monthly Contraceptive Injection) with that of a norethindrone 0.5, 0.75, 1.0 mg/0.035 mg ethinyl estradiol (NET/EE) triphasic oral contraceptive (Ortho-Novum 7/7/7). At study enrollment, women chose either the injections or the oral contraceptive. A higher proportion of women in the NET/EE group (65.1%) than in the MPA/E2C group (48.7%) had used hormonal contraception during the month before the study (p < 0.01). Overall, 55.5% (434/782) of MPA/E2C users and 67.6% (217/321) of NET/EE users completed the 60-week trial. One-year contraceptive efficacy (13 cycles of 28 days) for MPA/E2C and NET/EE was based on 8008 and 3434 woman-cycles of use, respectively. During the first year, one pregnancy occurred in an NET/EE user for a life table rate of 0.3; no pregnancies occurred in users of MPA/E2C. One additional pregnancy in the NET/EE group occurred during the 15th treatment cycle. After the first treatment cycle, women in both groups experienced regular menses, with an average cycle length of 28 days in MPA/E2C users and 27 days in NET/EE users. Although MPA/E2C users were more likely to experience bleeding irregularities, only 2.5% (19/775) cited metrorrhagia as a reason for discontinuing treatment. The adverse events reported in both treatment groups are consistent with those expected with the use of combined hormonal contraceptives. Overall, the results of this first Phase III US clinical trial of MPA/E2C confirm this method's high contraceptive efficacy and safety, as shown in previous studies by the World Health Organization. These results suggest that a monthly combination injectable would represent a welcome new contraceptive option for women in the US.

Contraceptive Agents, Female↗

PubMed2000

LQG controller design using GUI: application to antennas and radio-telescopes

The Linear Quadratic Gaussian (LQG) algorithm has been used to control the JPL's beam wave-guide, and 70-m antennas. This algorithm significantly improves tracking precision in a wind disturbed environment. Based on this algorithm and the implementation experience a Matlab based Graphical User Interface (GUI) was developed to design the LQG controllers applicable to antennas and radiotelescopes. The GUI is described in this paper. It consists of two parts the basic LQG design and the fine-tuning of the basic design using a constrained optimization algorithm. The presented GUI was developed to simplify the design process, to make the design process user-friendly, and to enable design of an LQG controller for one with a limited control engineering background. The user is asked to manipulate the GUI sliders and radio buttons to watch the antenna performance. Simple rules are given at the GUI display.

Journal Article↗

PubMed2003

Measuring therapeutic attitude among drug workers.

A reluctance of nonspecialists to work with drug and alcohol misusers have focused upon belief-based systems, including therapeutic commitment (TC) and situation-specific constraints. This paper describes the development and assessment of a theoretical model for nonspecialist drug workers, characterised as a synthesis of attitudinal and constraints explanations. A cohort of 189 nonspecialist drug workers completed self-report measures of overall TC and situational constraints scales. Predictive analysis of associations between TC, role security (RS), role requirements, and situational constraints was performed to explore direct and indirect effects. Such assessment allowed for the identification of a predictive process by which TC may be established, manipulated, and maintained. Levels of TC were found to be explained by the direct effects of self-esteem (SE), situational constraints, role support, and RS. Role support and situational constraints were also found to have indirect effects. Experience with working with drug users and education on drug-related issues were found to have predominantly indirect effects on TC via situational constraints and RS. Findings show the synthesised model to be partially supported. Implications for the development of a process-driven theoretical understanding of TC and situational constraints are discussed, and applied recommendations for training intervention are presented.

Adult↗

PubMed2004

Persistence of cognitive effects after withdrawal from long-term benzodiazepine use: a meta-analysis.

Despite the widespread prescribing of benzodiazepines, uncertainty still surrounds the potential for cognitive impairment following their long-term use. Furthermore, the degree of recovery that may take place after withdrawal or the level of residual impairment, if any, that is maintained in long-term benzodiazepine users is also unclear. The current paper employed meta-analytic techniques to address two questions: (1) Does the cognitive function of long-term benzodiazepine users improve following withdrawal? (2) Are previous long-term benzodiazepine users still impaired at follow-up compared to controls or normative data? Results of the meta-analyses indicated that long-term benzodiazepine users do show recovery of function in many areas after withdrawal. However, there remains a significant impairment in most areas of cognition in comparison to controls or normative data. The findings of this study highlight the problems associated with long-term benzodiazepine therapy and suggest that previous benzodiazepine users would be likely to experience the benefit of improved cognitive functioning after withdrawal. However, the reviewed data did not support full restitution of function, at least in the first 6 months following cessation and suggest that there may be some permanent deficits or deficits that take longer than 6 months to completely recover.

Benzodiazepines↗

PubMed1984

A low-cost chromatograph data-collection system.

A data collection system has been constructed, based on the low-cost BBC microcomputer, which provides for the digitization and storage of the data from one or more g.l.c. or h.p.l.c. instruments, or from other data sources with similar data rates. The data can be observed during collection on the graphics screen, and are then stored on disk for subsequent processing. This processing is designed to be interactive, so that the operator can influence decisions about base-line drifts, peak separations, etc. when integrating the peaks, and can decide which peaks are to be stored in a time/intensity record, on the basis of a visual display of the trace. A low cost multi-channel precision ADC, using isolated voltage-to-frequency transducers sited at the sources of data, and multiple counters at the computer, may be used to measure several signals simultaneously even when they originate at some distance from the computer, and extra memory can also be added to the BBC microcomputer to allow temporary storage of data. The software is written in machine code (for the data collection) and BASIC (for the analysis routines) so that modifications to the latter routines can be made easily. The user interface is suitable for routine users who have no computing experience.

Chromatography↗

PubMed1998

Mathematical shape matching as a tool in tooth wear assessment--development and conduct.

The quantitative assessment of restoration and tooth wear usually requires fixed reference points from which measurements are made. In longitudinal patient follow-up the loss or erosion of such points may preclude measurement and an alternative approach is to seek regions of coincidence and conflict in digital models of before and after wear surfaces, with a continuous refinement of the parameters of the coordinate transformations, until the closest correspondence between them is found. A computer program has been written to implement the algorithm and assess the technique's capacity to find the match between surfaces both artificially generated and from tooth replicas recorded from patients at different epochs. The program was able to achieve the desired ends, demonstrating the utility of the technique in tooth wear assessment but identifying the need to refine the program further to enhance both its difference detection capabilities and level of automation. Examination of the theory and practical experience highlighted certain situations when user understanding is invaluable to ensure a satisfactory solution. This strengthened the investigators' resolve against reliance upon commercially based surface fitting programs whose basis may not be fully understood. Notwithstanding this surface matching is a powerful tool in the investigation of dental wear.

Algorithms↗

PubMed2001

Implant contraception.

The experience of 6 million Norplant users has led to several more advanced implants. Implanon is a single-rod implant system containing a low androgenic progestin and requires 1 to 2 minutes for insertion and removal. Like other implants, Implanon prevents pregnancy by changing the character of the cervical mucus and interfering with luteal function. Unlike Norplant, though, Implanon is designed to prevent ovulation for the full duration of use. Implant contraception has several advantages over other types of contraception including high efficacy, minimal required maintenance, absence of estrogen, and rapid return of fertility after discontinuation. Implants can be a good choice for adolescents; women with hypertension, diabetes, anemia, endometriosis, or other medical problems; and women who are breast-feeding. Irregular bleeding is the most common adverse effect of implants and can be treated with several medication regimens. Preinsertion counseling, however, is the most important factor in ensuring satisfaction with implants. Unfortunately, no implant system is currently available in the United States since August 2000, but Implanon is expected to reach the U.S. market within the next 2 years.

Cervix Mucus↗

PubMed2005

Are waterpipe users interested in quitting?

Waterpipe smoking has increased dramatically worldwide in recent years, with an estimated 100 million daily users. Research on this traditional Middle Eastern tobacco use method is in its infancy, and little is known about users' cessation-related attitudes and experiences. A random sample of 268 narghile (waterpipe) smokers (40% female; mean age = 30 years; range = 18-68) was obtained from cafes and restaurants in Aleppo, Syria. The majority of users (86.5%) believed they could quit using waterpipes at any time, but that belief was inversely related to perceived dependence, with only 48.7% of those who thought they were "very hooked" believing they could quit. Interest in quitting was expressed by 28.4% of subjects, with the majority (89.2%) reporting health concerns as a primary reason, and 59.2% having made an unsuccessful quit attempt in the past year. In a logistic regression model, independent predictors of interest in quitting included being married, having smoked for fewer years, not increasing the frequency of smoking over time, and having family members who do not smoke a waterpipe and disapprove of its use. Results indicate that a sizable percentage of waterpipe users express interest in quitting and have tried unsuccessfully in the past to quit. Waterpipe use needs to be considered in developing effective tobacco use cessation programs in the Middle East.

Adult↗